Air-spring device



J. J. MCELRQY AIR SPRING DEVICE Filed Sept. 3, 1924 2 Sheets-Shea?. l

oct. 12 1926.

J. J. MGELROY AIR SPRING DEVICE Filed sept. 5. 1924 2 Sheets-Sheet 2 I I g HIS ATTORNEYS' Patented Oct. 12, 1926.

UNITED STATES 1,602,539" PATENT oFFlcE.,

TOENy J. MCELROY,.OF NEW HAVEN, CONNECTICUT, ASSIGNOB, TO THEWESTINGHOUSE AIR SPRING COMPANY, OF NEW HAVEN, CONNECTICUT, A CORPORATION F PENN- SYLVANIA.

A 1a-SPRING nnvrcn. q

Application ld September 3, 1924. Seria1 No. 735,559.

My present 'invention relates to method and means for sealing the joints between the parts of the compression chambers of pneumatic springs such as are used for vehi- 5 cles. It relates particularly to the methodl and means for producing such seals which comprises forming the elements of the spring structure to provide basins or liquid-collecting pockets at the seams or joints of such compression chambers `and Iliquid for such pockets. y

In such' devices slow or rapid leaks decrease the eliciency thereof, but I have disby nut 6. The piston head 7 held by nut 8 and washer 9 on rod 3 holds against block 5 the packing ring 10.- The expander' '11 serves to hold said ring 10 against the sides of the cylinder and'is held in 'the 60 expanding position by the spring 12, the expander, spring, and ring being positioned beneath the main portion of said head 7 s and about a portion thereof of reduced diameter. The piston follower 13 screwed on 65 said rod 3 below said head 7 holds\between it and sleeve 14 the second packing ring 15 which 1s provided with an expander 16 covered that in cases where increased caeJad an expander spring 17. The cavity 20 5 in the manufacture and testing of the devices is ineffective in cutting down the numbers of such leaks or is prohibitive in cost that they canbe overcome economically by providing the seams of the chambers which are 0 subjected to increased pressure with means for holding sealing-liquid thereat.

It is therefore an object of my invention to provide a pneumatic cushion device with a compression chamber? all of the seams of which are provided with liquid seals.

It is also an-object of my invention to provide an aircushion in which a cylinder and a piston bound a compression-chamber and in which oil is used to lubricate the contacting surface of said piston and cylinder with means for trapping oil splashed by said piston and holding it at the seams to provide oil seals thereat.

V Other objects of my invention will be '35 apparent from the specification and from the drawings, in which Fig. 1 is an elevational view of an air spring embodying features of my invention. ig. 2 is an elevational view in section along the line 22 of Fig. 1, showing an air spring with a piston A'having formed therein pumping means for forcing oil collected between the piston packing rings thereof back into the compression chamber, and with means at the seams of said com,- pression chamber for collecting and holding oil thereat to effect the sealing thereof.

Fig. 3 is an elevational view along the line 3 3 of Fig. ,1 of similar device in" which is employed a simple piston..

In Figs. 1 ,and2 of the drawings is shown an air spring comprising a cylinder 1 Within which works the piston 2 carried by the piston rod 3. Said 4piston -2 comprises the piston block 5 held on saidLrod 3 ..24 and 2.5 with the in rod 3 is closed by plug 21 and the cavities 70 22, 22 in block 5 connect' through openings piston ring cavities and serve to accumulate a head of air by theL lcontinued leakage of oil und-er pressure from the chamber 26 during the action of the 75.

air spring suiicient to force oil accumulated in such ring cavities upwardly back into the cushion chamber- 26 of the air spring, which occurs when the pressure in the cavities 20, 22, 22 is greater than the S0 lowest pressure in the `chamber 26 at the eXtre e outer stroke of the piston 2.'

Said chamber 26 is bounded at its top and part of its sides by the cylinder cap 27 which has a greater maximum diameter than the S5 said cylinder but has a smaller diameter at its lower extremity wherebytit is screwed about the outsidel of said. cylinder. 'The point of attachment of saidrcap 27 to the cylinder is considerably below the upper exx' tremity of the cylinder, whereby is formed an annular pocket 30 at the lvseam of their juncture in which oil splashed by the piston collects to form a seal for said seam. I-Ioles 31, 31 in said cylinder at an appreciable 95 distance above said seam serve to allow eX- cess oil to flow back and forth into the cylinder. v

The cup 35 depending from theN body 36 of air valve 37 and communicating with the 100 main bore thereof (see Fig. 3) serves to hold a charge of oil which upon any leakage of. said valve 37 will be drawn up into the valvel and eifectually seal it 'at its seat to prevent furtherleakage. A charge-of oil in said cup 1,05 35 is maintained therein by being replen.` ished through the splashing lof oil thereinto by said piston during its action.

The cylinder is mounted by being screwed into the cup member40 at a point aboveits U0 ,lower end, the bottom offsaid cup serving said bottom provides proper bearing surface for said rod. The bushing is drilled at 42 near ythe bottom of the interior of cup 40 to allow oil to flow to lubricate the rod andv bushing. The felt washer 43 serves to hold oil whichwill flow for such lubrication and the rubber washer 44 serves as a bumper for the bottom of the piston 2 during eX- treme movement thereof. 'Ihe shackle 45' serves to connect the piston rod to a steel spring of a vehicle and the bolts 46, 46 serve to mount the cylinder to the' chassis thereof.

In Fig. 3 is shown a. device similar to that of Fig. 2 but having a piston without pump chambers and with the cylinder mounted at Iits end to the cup In the use and operation of the device of my invention chamber 26 is provided with valve as described, nd when the piston is in suliicient oil to sepocket 30, to Vseal the the down position to gver the head thereof in the cylinder and thereby seal the joint therebetween. In the extreme up position, as shown in the drawings, the oil will extend over the ends of the cylinder by being displaced by the piston or will flow through holes 31 into the annular oil channels 50 formed in head 7 to thereby eect a liquid seal between the piston and cylinder.

recata@ In Fig. 4` is shown an oil seal between the valve housing 37 and the cap dome 26 comprising the skirt 55 on said housing which depends into the annular channel 56 bounded by rim 57 which is formed in the inside of the housing receiving opening in said cap. Oil 58 splashed by the piston serves as the seal between the cap and the housing.

I claim- 1 1. An air spring device comprising a cylinder, a cap joined to said cylinder, a piston in said cylinder, an air valve for the chamber `formed by said members, and an oil seal for the cylinder and cap joint, for the cylinder and piston sliding joint, and for the air valve. i

2. An air spring device comprising a cylinder, a cap joined to said cylinder, a piston in said cylinder, an oil seal for the cylinder and cap joint and for the cylinder and pis` ton sliding joint, and a pump for returning escaped fluid through the piston seal tothe chamber above the piston.

3. An air spring device comprising a cylinder, a cap joined to said cylinder, a piston in said cylinder, a pump for returning escaped fluid to the chamber above the piston, an oil seal for the cylinder and cap joint. and for the cylinder and piston sliding joint,and an air valve for'the said chamber and an oil seal for said air Valve.

4. An air spring device comprising a cylinder, a cap joined to said cylinder, a piston in said cylinder, an air valve for the chamberformed by said members, and an oil seal for the cylinder and cap joint, for the cylinder and piston sliding joint, for the valve housing and cap joint, and for the air valve.

In testimony whereof I hereto- -ax my signature.`

John a. Mouriiior.

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